Textile and other materials and process for their production



Patented May 2 3, 1939 v UNITED STATES PATENT OFFICE TEXTILE AND OTHER MATERIALS AND PROCESS FOR THEIR PRODUCTION Henry Dreyfus, London, England No Drawing. Application March 28, 1936, Serial No. 71,457. In Great'Britain April 9, 1935 6 Claims. (Cl. 8-129) This invention relates to improved textile and hydridaand in a similarwaythe delustre produced other materials and process for their production. in either artificial silks of organic derivatives of Commercial cellulose acetate artificial silk is cellulose by hot aqueous treatments may be renreadily delustred by hot or boiling water or other dered resistant to ironing by acetylation or other aqueous liquors or by moist steam. This process esterification, 5 forms the basis of a commercial production of The acetylation or other esterification is prefdelustred artificial silks, the common commercial erably eifected with the aid of an acid anhydride, process being to treat the artificial silk in a boiling for example acetic anhydride, propionic anhysoap solution for upwards of half an hour. The dride, etc. The anhydrides are, in the pure state,

10 degree of lustre remaining on the material desolvents for the artificial silks to be treated and, 10 pends upon the temperature and time of treatin order to prevent solution or even incipient solument, so that various degrees of lustre are obtaintion, must be diluted with appropriate agentsable from a completely matt appearance to a which repress the solvent power of the anhydrides. lustre little short of that of the artificial silk as In order to obtain the effect of the present inspun, vention, the degree of dilution must be such that 15 Similarly, artificial silks made from other the original lustre of the artificial silk is not organic derivatives of cellulose, for instance celrestored by the acetylation or other esterlficalulo'se propionate and methyl or ethyl cellulose, tion, and is preferably such that there is little or are delustrable by means of hot or boiling aqueous no change in the lustre. By this means, the

2 liquors or moist steam. final lustre in the artificial silk may be predeter- The low lustre of the cellulose acetate artificial mined by an adjustment of the temperature and silk or of similar artificial silks produced by these t me o tr a in the 11015 aqueous media. d processes is, However, not permanent to various this degree of delustre remains in the aftertreatments to which the materials are commonly treatment.

subjected either in subsequent processes of manuneral y, hydr car ons and the non-solvent 25 facture or in laundering operations. In particuchlorinated hydrocarbons are the most suitable lar the lustre is more or less crestored by ironing diluents for the purp se of e p n i e o the materials in a wet condition. The present for example be ne, toluene, y e d t e invention has as its object to render the delustrher homologues of benzene, kerosene and I ing produced by hot or boiling aqueous liquors or other higher boiling petroleum hydrocarbons, car- 80 moist steam resistant to ironing and to other bon tetrachloride and the like. The higher alitreatments. phatic ethers are also useful as diluents. Dilu- I have found that an acetone-soluble cellulose tion of acetic anhydride with some twenty times acetate artificial silk which has been delustred s weight of xyl r h r aromatic y r a may be subjected to a process of acetylation so as bOn or chlorinated hydrocarbon is suflicient to 85 to increase its acetyl content while substantially prevent y Substantial a e in t e lustre when retaining the low lustre of the artificial silk, and the acetylatio is Ca d out at the boiling point further that the treatment renders the lustre 0f the mix r The invention is w ve progressively resistant to change by ironing wet, limited to such proportions and the amount of 40 At the same time, depending upon the degree of u t y e y q y, c as five or ten acetylation, the resistance of the material to heat times up t w y times or more the q y f treatments is increased so that the product of the e a y which Will Prevent sto a on of present invention may be ironed without damage the lustre of the artificial silk, and is preferably at higher temperatures than ar customary in such that there is no substantial change in the 5 ironing ordinary cellulose acetate artificial silk. lustre. The best proportions to use depend partly 5 Again according to the degree of acetylation, on the nature of the anhydride and of the diluent the resulting material is more or less resistant and on the temperature of treatment. to further delustring by hot or boilingaqueous The reaction is preferably eiiected in the presliquors and, in addition, its aflinity for dyestufis, ence of a suitable catalyst which may be any 5 and in particular for the dispersed insoluble dyeof the ordinary catalysts used in the acetylation stuffs now customarily applied to cellulose acetate of cellulose, but in order to increase the heat artificial silk, is modified. resistance of the materials it is preferable not The same effect may be produced by esterifying to use sulphuric acid, phosphoric acid, and other the acetone-soluble cellulose acetate artificial silk dior poly-basic acid catalysts or derivatives 1 with ester-flying agents other than acetic anthereof which tend to combine with cellulose in dissolved in the reaction mixture or may be ap-.

' plied to the artificial silk before immersion in the reaction mixture. For example, the artificial silk may be treated with an aqueous or other solution of sodium or potassium acetate, and the catalyst dried out in the material before immersion in the acetylation mixture.

As previously indicated, the effect obtained is to some extent dependent upon the degree of esterification or further esterification brought about in the process of the invention. Generally the degree of esterification may be adjusted by using the appropriate amount of acetylating or other esterifying agent and/or by an adjustment of the temperature or time of treatment. In the case of acetylating delustred cellulose acetate artificial silk, a treatment at the boil for half an hour with a mixture containing a quantity of acetic anhydride equal to l-2 times the weight sodium acetate in the cold, centrifuging and drying.

The treatment according to the present'invention may be applied to the artificial silk in any suitable form, for example to yarn in the form of hanks or in the form of open wound packages through which the reaction mixture is pumped or sucked, or in the form of woven, knitted or other fabrics. A previous impregnation with the catalyst may be carried out continuously with the acetylation or other est-erification. By carrying out the reaction under a pressure in excess of atmospheric pressure, the reaction temperature may be raised above the boiling point of the anhydride or of the diluent, and in consequence shorter times of treatment may be used.

In addition to rendering the more or less low lustre of artificial silk more resistant to wet ironing for example, the treatment of the present invention improves the resistance of the material to heat generally, so that dry ironing may be carried out at a higher temperature, and also modifies the aflinity of the materials for dyestuffs. Thus, materials treated in accordance with the invention may be associated in doubled yarns, cords or similar materials or in fabrics, with untreated materials, so as to obtain a mixed textile material which, while exhibiting as a whole an aflinity for certain types of dyestufi, for instance the dispersed insoluble colours, is nevertheless capable of being dyed in different shades by immersion in a dyebath containing a single dyest'uif, owing to-the differential afiinities of the different materials constituting the goods. Further colour efbe removed on immersion fects may be obtained by'associating the products of the present invention, with or without artificial silks of cellulose derivatives which have not been treated, with other types of materials, such as cotton, the regenerated cellulose type of artificial silk, or'animal fibres. I

Local effects may be produced according to the present invention by the local application of the reagents. For example, a fabric may be printed in a design with a wax or other suitable resist, the unprinted portion delustred by treatment of the fabric in a boiling soap solution, the wax or other ground is obtained. If the acetylation or otheresterification mixture is suitable, the resist may reaction mixture. I

While the invention has been described above more particularly with reference to the treatment of textile materials, itmay also be applied to the treatment of films, foils and similar materials of cellulose derivatives where a permanent delustred appearance is desired. For instance, a,

translucent wrapping foil may be produced by the present invention which does not become transparent when sealing is eifected by means of heat treatment.

The products of the present invention are novel. As compared with ordinary bright artificial silk, they present a dull lustre and have, under a lens, the crazed appearance characteristic of cellulose acetate artificial silk which has of the material in the been delustred by means of boiling water or moist steam, and, at the same time, they are differentiated from this known delustred product by being resistant to relustring on ironing wet.

The following examples illustrate the invention but are not to be considered as limiting it in any way:

' Example 1 A cellulose acetate artificial silk fabric is delustred by boiling in a 0.25% soap solution at the boil for -1 hour, depending on the degree of delustre required. The fabric is then treated for about 1 hour at 20-25 C. in a solution containing, per 100 parts of fabric, 150 parts of acetic anhydride, 2000-3000 parts of benezene, and 3 parts of crystallised ferric chloride. The fabric after treatment is removed, washed first with benzene, then with water and dilute alkali to remove traces of acid, and finely dried.

Example 2 Afabrlc, delustred as in Example 1, is acetylated as described in Example 1, but using instead of 3 parts of crystallised ferric chloride a cata'.yst comprising 1 part of crystallised ferric chloridev and 2' parts of hydrogen chloride. The treatment is otherwise the same.

Example 3 Example 4 A fabric, delustred as described in Example 1, is impregnated with a solution containing 35-40% of sodium acetate, and is then centrifuged and Example 5 A cellulose acetate artificial silk fabric is printed in any suitable design with molten resin or colophony. The-print is cooled to allow the resin to solidify, and the fabric is then treated in water at 90-95 C. until the desired degree of delustre is produced' The fabric is then rinsed and the resin removed, for example by treatment with xylene or other suitable solvent. The fabric is then acetylated according to any of the preceding examples.

The products of Examples l-4 are all delustred fabrics which present the crazed appearance characteristic of ordinary delustred cellulose acetate artificial silk, but are all resistant to relustring on ironing wet. Further, the treatment has raised the resistance of the fabric to heat. The product of Example 5 is also more resistant to heat than the starting material, but the permanent delustre is in a design on a lustrous background. In a similar way, delustred cellulose acetate artificial silk or delustred cellulose acetate foil may be treated with other ester'ifying agents, for example propionic or butyric anhydride, and, further, delustred material of other organic derivatives of cellulose may be acetylated or otherwise esterified.

Having described my invention, what I desire to secure by Letters Patent is:

'1. Process for the production of artificial materials of reduced luster which is not increased by ironing while wet, which comprises reducing the luster of textile materials, foils, films and similar materials made of organic substitution derivatives of cellulose soluble in organic solvents, by subjecting them to the action of hot aqueous media, and subsequently esterifying the materials of reduced luster, the structure of the 3. Process for the production of artificial materials of reduced luster which is not increased by ironing while wet, which comprises acetylating textile materials, foils, films and similar materials made of acetone-soluble cellulose acetate, the luster of which hasbeen reduced by hot aqueous media, by subjecting them to treatment in a liquid non-solvent acetylation medium comprising acetic anhydride dissolved in a non-solvent diluent in the presence of stannic chloride as catalyst.

4. Process for the production of artificial materials of reduced luster which is not increased by ironing while wet, which comprises acetylating textile materials, foils, films and similar materials made of acetone-soluble cellulose acetate,

the luster of which has been reduced by hot aqueous media, by subjecting them to treatment at a temperature of about 20 to 25 C. in a liquid non-solvent acetylation medium comprising acetic anhydride dissolved in'a non-solvent diluent selected from the group consisting of liquid hydrocarbons and halogenated hydrocarbons in the presence of ferric chloride as catalyst, the amount of acetic anhydride being from 5 to 20% of the amount of non-solvent diluent.

5. Process for the production of artificial materials of reduced luster which is not increased by ironing while wet, which comprises reducing the luster of textile materials, foils, films and similar materials made of acetone-soluble cellulose acetate, bysubjecting them to the action of hot aqueous media and subsequentlyacetylating the materials of reduced luster by subjecting them to treatment at a temperature of about 20 to 25 C. in'a liquid non-solvent acetylation medium comprising acetic anhydridedissolved in a non-solvent diluent selected from the group consisting of liquid hydrocarbons and halogenated :hydrocarbons in the presence of ferric chloride as catalyst, the amount of acetic anhydride being from 5 to 20% of the amount of non-solvent diluent.

6. Process for the production of artificial ma- 

